Convertible rail-highway vehicle

ABSTRACT

Means for retaining flanged wheels in contact with rails on a convertible rail-highway vehicle in which traction is effected through the normal highway-engaging pneumatic tired wheels riding on the rails, utilizing a load transfer arm pivoted to the chassis of the vehicle in such a way that a portion of the weight of the vehicle is applied to the flanged wheels thereby reducing danger of derailment.

a f: 2|? Unite States atent 51 3,638,580 Yard Feb. 1, 1972 [54]CONVERTIBLE RAIL-HIGHWAY [56] References Cited VEH ICLE UNITED STATESPATENTS [72] Inventor: William James Yard, Cavan, Australia 2 039 4895/1936 Messick [05/215 C [73] Assignee: Aresco Trek-Chief ProprietaryLimited, 1,938,049 12/1933 Serrano.. ...105/215 C Cavan South AustraliaAustralia 2,016,626 10/1935 Constantmesco..... ....105/2l5 2,655,87210/1953 Templeton ..105/2l5 C [22] Filed: Mar. 4, 1970 PrimaryExaminer-Arthur L. La Point [21] 16368 Assistant Examinerl-lowardBeltran Attorney-Oldham & Oldham 30 Forei A l' ation P it D ta I W y a57 ABSTRACT Mar. 4, 1969 Australia ..51,409/69 Means for retainingflanged wheels in Contact with rails on a convertible rail-highwayvehicle in which traction is effected [52] US. Cl. .l05/2l5 C, 105/174,105/224 R through the norma] highway engaging pneumatic med wheels [51]f 15/00 B6lf9/OO, 362d 61/12 riding on the rails, utilizing a loadtransfer arm pivoted to the Fleld of Search 215 4 R chassis of thevehicle in such a way that a portion of the weight of the vehicle isapplied to the flanged wheels thereby reducing danger of derailment.

6 Claims, 5 Drawing Figures Pmmanraa 1 1972 3538.580

SHEET 1-092 INVENTOR \/\LL\AM JAMES YARD ATTO RN E YS CONVERTIBLERAIL-HIGHWAY VEHICLE This invention relates to rail engagement means forthe engagement of the rails of a permanent way of a vehicle which isarranged to travel either by highway or by rail.

It has been proposed to employ a convertible rail-highway vehicleprovided with retractable rail engagement wheels so that the vehicle canbe driven over a highway on pneumatic tires or alternatively along railswhen the pneumatic tires are used for traction purposes only, theretractable flanged wheels being lowered to engage the rails so as toretain the vehicle on the rail track.

With previously proposed convertible rail-highway vehicles a problem hasexisted in that a heavily laden vehicle can under some circumstancesbounce on its pneumatic tires and thereby become derailed, and one ofthe objects of this invention is to provide means whereby a load isapplied to the retractable flanged wheels urging them into engagementwith the rails in such a way that the danger of derailment issubstantially reduced.

In one of its forms the invention may include a longitudinally extendingload transfer arm on each side of the vehicle chassis, pivot meanspivotally supporting each load transfer arm intermediate it ends to thechassis, and traction wheel support means and shiftable flanged wheelsupport means both carried on each load transfer arm but spaced fore andaft of the pivot means, whereby part of the load of the vehicle issupported by the traction wheels and part is supported by the shiftableflanged wheels. By this means any dead load applied to the arm (staticloading) will be partly taken by the pneumatic tired traction wheel andpartly taken by the shiftable flanged wheels, while any dynamic loadwill be similarly distributed thereby reducing danger of derailment ofthe vehicle for any reason (for example rail irregularity). If a loadsupport spring is interposed between the shiftable flanged wheel and theload transfer arm, the shiftable flanged wheel can be retained against arail notwithstanding wheel bounce.

Although constructional details of the invention can vary considerablywithin this invention, an embodiment is described hereunder in somedetail with reference to and is illustrated in the accompanyingdrawings, in which:

FIG. 1 illustrates diagrammatically a convertible railhighway vehicle ona highway but adjacent a rail track,

FIG. 2 illustrates diagrammatically the vehicle positioned above thetrack and swing around on a retractable turntable to align with thetrack,

FIG. 3 is an enlarged fragmentary elevational view showing rear tractionwheels and a rear shiftable flanged wheel in engagement with a rail,

FIG. 4 is a similar view, but in section, and

FIG. 5 is a perspective view showing an arrangement for driving a wedgebeneath one end of the load transfer arm.

According to this embodiment a heavy duty convertible rail-highwayvehicle is provided with two rear axles 11 each carryinghighway-engaging pneumatic tired traction wheels 12. The wheels areinterconnected by means of a spring support arm 13 which transfers theload from the rear end of the front springs to the rear end of the rearsprings, this being a known arrangement. A fixed pivot pin 16 pivotallysupports each of the spring support arms 13 to the chassis of thevehicle, each pivot pin 16 being pivoted in its arm between the ends ofthe arm in such a way that some of the weight of the vehicle is borne oneach of the rear traction wheels 12. Each pivot pin 16 is secured to andextends outwardly from a respective secondary load transfer arm 17.

In this embodiment a pair of rearwardly extending secondary loadtransfer arms 17 are employed, each being pivoted intermediate its endson a respective pivot pin 20 extending outwardly from and secured to themain chassis 22 of the vehicle 10. Each secondary load transfer arm 17is pivoted to a respective spring support arm 13, utilizing the samepivotal axis as was previously employed for carrying the spring supportarm 13 from the chassis, the old pivot means between the spring supportarm and the chassis however being removed.

The rear end of each of the secondary load transfer arms 17 pivotallysupports a rear frame 25 which carries in it bearings 26 (FIG. 4) inwhich is journaled a transverse axle 27 carrying shiftable flangedwheels 28 on each end. When the secondary load transfer arm 17 is in itsdown position, the shiftable flanged wheels 28 engage the rails 30 of apermanent way. The axle is supported through suspension springs 31.

The frame 25 which carries the shiftable flanged wheels is coupled tothe secondary load transfer arm by a retracting cylinder 33, thisretracting cylinder being operable to tilt the frame about apivotal-mounting pin 34 so that the shiftable flanged wheels are liftedclear of the rails.

The forward end of each of the secondary load transfer arms 17 projectforwardly of the pivot pin 16 about which they are coupled to theprimary spring support arms 13, and is provided with a recess portionarranged to accommodate a sliding wedge 38 (FIG. 5). Each wedge iscarried in slides 39 fixed to the chassis, and is arranged with a singlecylinder 40, the cylinder then expanded driving the wedge outwardlythereby firmly fixing the respective secondary load transfer arm 17against any pivotal movement relative to the chassis. In this way theforward pivot pin 16 between the spring support arm and secondary loadtransfer arms become fixed relative to the chassis, and the vehicle canoperate in a normal way on its highway-engaging pneumatic tired wheels.However when the retracting cylinder is retracted and wedge iswithdrawn, the secondary load transfer arm is capable of pivoting aboutits pivotal interconnection with the chassis and this then transferssome of the vehicle load from the traction wheels on to the shiftableflanged wheels. If the proportion of lengths between the three pivotalaxes along the secondary load transfer arm is say, in the proportion of6:4, then 40 percent of the load of the vehicle can be applied to theshiftable flanged wheels and 60 percent to the traction wheels, thisbeing a typical suitable proportion for average operating conditions.

Under dynamic conditions it is clearly desirable that the shiftableflanged wheels should be locked in their position relative to the loadtransfer arm, and to achieve this the rear frame 25 has forwardlyprojecting lugs 43 (FIG. 4) which are apertured and the apertures in theforwardly projecting lugs align with corresponding apertures in thesecondary load transfer arm 17, and these aligned apertures have lockingpins 44 passing therethrough. In this embodiment the locking pins areformed to be a neat fit in the aligned apertures, and the pins areprovided with outstanding bars which are arranged to rotate intoreceiving sockets (not shown), thus preventing inadvertent release ofthe pins under operating conditions.

The above embodiment has been described in relation to a heavy dutyvehicle having a pair of back axles to carry pneumatic tiredhighway-engaging wheels. However it will be seen that the invention isequally applicable to a vehicle having a single back axle, in which casethe pivot point between the ends of the axle remains unchanged, and thesingle back axle load is transferred as previously to the front end ofthe secondary load transfer arm (which in such a case becomes the onlyload transfer arm), and locking means again are provided as previously,the locking means being operable when the shiftable flanged wheels arein their retracted position.

What I claim is:

1. Road engagement means for a convertible rail-highway vehicle having achassis with pneumatic tired rear traction wheels and adjacent rearflanged wheels, comprising:

a longitudinally extending load transfer arm on each side of the vehiclechassis;

pivot means connecting each load transfer arm intermediate its ends tothe chassis;

first suspension means pivotally connected to the load transfer armbetween the pivotal connection of the arm to the chassis and a first endof the am, the first suspension means being connected to the tractionwheels; and shiftable second suspension means connected to the other endof the load transfer arm and on the opposite side of the pivotalconnection between the arm and the chassis from the first suspensionmeans, the second suspension means being connected to the flangedwheels,

2, Rail engagement means according to claim 1 further comprising a lockmember releasably engaging the load transfer arm locking the loadtransfer arm against movement about its pivotal support means when thetransfer arm is engaged but releasing the transfer arm forpivotalmovement when the locking means is disengaged.

3. Rail engagement means according to claim 1 comprising a slide membersecured to the vehicle chassis, a hydraulic cylinder coupled at one endto theslide member, said lock member being a wedge-shaped lock memberguided for movement in the slide member and coupled to the other end ofthe hydraulic cylinder, the wedge-shaped lock member being movable undercontrol of the hydraulic cylinder to engage the load transfer armlocking the load transfer arm against movement about its pivotal supportmeans but retractable to release the load transfer arm for pivotalmovement,

4. Rail engagement means according to claim I, further comprising apivot pin connecting the load transfer arm with suspension springs ofthe pneumatic tired traction wheels.

5. Rail engagement means according to claim 1, comprising further pivotmeans on the load transfer arm, a frame pivotally supported by thefurther pivot means, bearings-guided for movement in the frame and urgeddownwardly by suspension springs, an axle extending through the bearingsand carrying said rail-engaging wheels, and means to retain the frameagainst pivotal movement with respect to the load transfer arm.

6. Rail engagement means according to claim 5, further comprising aretracting cylinder operably coupiing said pivoted frame and loadtransfer arm and arranged to pivot the frame to a position where therail-engaging wheels are retracted from engagement with the rails.

1. Road engagement means for a convertible rail-highway vehicle having achassis with pneumatic tired rear traction wheels and adjacent rearflanged wheels, comprising: a longitudinally extending load transfer armon each side of the vehicle chassis; pivot means connecting each loadtransfer arm intermediate its ends to the chassis; first suspensionmeans pivotally connected to the load transfer arm between the pivotalconnection of the arm to the chassis and a first end of the arm, thefirst suspension means being connected to the traction wheels; andshiftable second suspension means connected to the other end of the loadtransfer arm and on the opposite side of the pivotal connection betweenthe arm and the chassis from the first suspension means, the secondsuspension means being connected to the flanged wheels.
 2. Railengagement means according to claim 1 further comprising a lock memberreleasably engaging the load transfer arm locking the load transfer armagainst movement about its pivotal support means when the transfer armis engaged but releasing the transfer arm for pivotal movement when thelocking means is disengaged.
 3. Rail engagement means according to claim1 comprising a slide member secured to the vehicle chassis, a hydrauliccylinder coupled at one end to the slide member, said lock member beinga wedge-shaped lock member guided for movement in the slide member andcoupled to the other end of the hydraulic cylinder, the wedge-shapedlock member being movable under control of the hydraulic cylinder toengage the load transfer arm locking the load transfer arm againstmovement about its pivotal support means but retractable to release theload transfer arm for pivotal movement.
 4. Rail engagement meansaccording to claim 1, further comprising a pivot pin connecting the loadtransfer arm with suspension springs of the pneumatic tired tractionwheels.
 5. Rail engagement means according to claim 1, comprisingfurther pivot means on the load transfer arm, a frame pivotallysupported by the further pivot means, bearings guided for movement inthe frame and urged downwardly by suspension springs, an axle extendingthrough the bearings and carrying said rail-engaging wheels, and meansto retain the frame against pivotal movement with respect to the loadtransfer arm.
 6. Rail engagement means according to claim 5, furthercomprising a retracting cylinder operably coupling said pivoted frameand load transfer arm and arranged to pivot the frame to a positionwhere the rail-engaging wheels are retracted from engagement with therails.